Re: [dpdk-dev] [PATCH v8 6/6] build: use dependency for pcap and fallback to find_library

[Luca Boccassi <bluca@debian.org>]

On Fri, 2019-03-01 at 14:13 +0100, Thomas Monjalon wrote:
> 28/02/2019 18:40, Bruce Richardson:
> > On Wed, Feb 27, 2019 at 01:53:32PM +0000, Bruce Richardson wrote:
> > > On Wed, Feb 27, 2019 at 12:03:48PM +0000, Luca Boccassi wrote:
> > > > On Wed, 2019-02-27 at 11:56 +0100, Thomas Monjalon wrote:
> > > > > 27/02/2019 11:50, Luca Boccassi:
> > > > > > On Wed, 2019-02-27 at 09:47 +0000, Bruce Richardson wrote:
> > > > > > > On Wed, Feb 27, 2019 at 09:33:12AM +0100, Thomas Monjalon
> > > > > > > wrote:
> > > > > > > > 26/02/2019 18:49, Luca Boccassi:
> > > > > > > > > On Tue, 2019-02-26 at 17:46 +0000, 
> > > > > > > > > luca.boccassi@gmail.com
> > > > > > > > > wrote:
> > > > > > > > > > From: Luca Boccassi <luca.boccassi@microsoft.com>
> > > > > > > > > > 
> > > > > > > > > > pcap has historically shipped a custom pcap-config
> > > > > > > > > > binary
> > > > > > > > > > tool
> > > > > > > > > > which
> > > > > > > > > > does the job of pkg-config. It was never compatible
> > > > > > > > > > with
> > > > > > > > > > cross
> > > > > > > > > > compilation.
> > > > > > > > > > Meson uses it when using dependency(), which then
> > > > > > > > > > means
> > > > > > > > > > cross
> > > > > > > > > > compilation fails.
> > > > > > > > > > Set pcap-config to empty in the meson cross
> > > > > > > > > > compilation
> > > > > > > > > > files
> > > > > > > > > > so
> > > > > > > > > > that Meson will not use it, and add a fallback in
> > > > > > > > > > case
> > > > > > > > > > dependency() fails.
> > > > > > > > > > libpcap 1.9.0 finally ships a pkg-config file so
> > > > > > > > > > everything
> > > > > > > > > > will
> > > > > > > > > > work out of the box in the future.
> > > > > > > > > > 
> > > > > > > > > > Signed-off-by: Luca Boccassi <
> > > > > > > > > > luca.boccassi@microsoft.com>
> > > > > > > > > > ---
> > > > > > > > > > v8: added back pcap change separately. Tested with
> > > > > > > > > > bootlin
> > > > > > > > > >     cross-compilation toolchain, everything seems
> > > > > > > > > > to work.
> > > > > > > > > 
> > > > > > > > > I had some time to invest so I added back this
> > > > > > > > > change, in a
> > > > > > > > > way
> > > > > > > > > that
> > > > > > > > > works with cross compilation too. Given the series
> > > > > > > > > wasn't
> > > > > > > > > merged
> > > > > > > > > yet
> > > > > > > > > and there was a conflict I've done a v8 rather than a
> > > > > > > > > single
> > > > > > > > > separate
> > > > > > > > > patch, but it's independent from the rest.
> > > > > > > > > 
> > > > > > > > > More testing is of course welcome!
> > > > > > > > 
> > > > > > > > I still see the same error when cross-compiling:
> > > > > > > > 
> > > > > > > > /usr/include/stdint.h:109: error: "__INT64_C" redefined
> > > > > > > > 
> > > > > > > Can patches 1-5 be merged anyway, leaving 6 for later?
> > > > > > > 
> > > > > > > /Bruce
> > > > > > 
> > > > > > Yes please...
> > > > > 
> > > > > Yes, sure. I am checking other patches to push them.
> > > > 
> > > > Thanks!
> > > > 
> > > > > > Thomas, could you please give me detailed instructions on
> > > > > > how to
> > > > > > repro?
> > > > > > I used the bootlin toolchain you linked me last time, and
> > > > > > passed --
> > > > > > cross-file config/arm/arm64_armv8_linuxapp_gcc to Meson,
> > > > > > and
> > > > > > everything
> > > > > > built fine both with and without an arm64 build of libpcap
> > > > > > in the
> > > > > > sysroot. With the previous version that I removed it would
> > > > > > fail.
> > > > > > Not
> > > > > > sure what I'm missing!
> > > > > 
> > > > > I'm running devtools/test-meson-builds.sh on my ArchLinux
> > > > > which has
> > > > > aarch64-linux-gnu-gcc 8.2.0 but no arm pcap I guess.
> > > > 
> > > > The script is working fine too - I have the toolchain in /tmp
> > > > so I
> > > > simply run it with PATH=/tmp/toolchain/bin:$PATH and everything
> > > > built
> > > > fine including the arm targets.
> > > > 
> > > > The key part in the patch was adding pcap-config = '' to the
> > > > various
> > > > arm configs, could you please double check that it was applied
> > > > correctly? Without that, Meson finds and calls the native pcap-
> > > > config
> > > > which gives wrong (native) flags and causes the errors you are
> > > > seeing.
> > > > Otherwise I'm a bit lost, I can't understand why it's all
> > > > working here
> > > > and not there.
> > > > 
> > > > meson --werror -Dexamples=all --default-library=shared --cross-
> > > > file config/arm/arm64_armv8_linuxapp_gcc
> > > > /home/bluca/git/dpdk/devtools/.. build-arm64-armv8
> > > > The Meson build system
> > > > Version: 0.49.2
> > > > Source dir: /home/bluca/git/dpdk
> > > > Build dir: /home/bluca/git/dpdk/build-arm64-armv8
> > > > Build type: cross build
> > > > Project name: DPDK
> > > > Project version: 19.05.0-rc0
> > > > Native C compiler: ccache gcc (gcc 8.2.0 "gcc (Debian 8.2.0-21) 
> > > > 8.2.0")
> > > > Cross C compiler: aarch64-linux-gnu-gcc (gcc 7.3.0)
> > > > Host machine cpu family: aarch64
> > > > Host machine cpu: armv8-a
> > > > Target machine cpu family: aarch64
> > > > Target machine cpu: armv8-a
> > > > <...>
> > > > $ file build-arm64-armv8/lib/librte_eal.so.9.1 
> > > > build-arm64-armv8/lib/librte_eal.so.9.1: ELF 64-bit LSB pie
> > > > executable, ARM aarch64, version 1 (SYSV), dynamically linked,
> > > > not stripped
> > > > 
> > > 
> > > I'm testing on Fedora 29 and this patch works fine with the
> > > cross-builds
> > > too. Maybe it's something special in Arch Linux again. I'll
> > > trying testing
> > > it out in an Arch VM - though sadly Arch linux is failing to
> > > update for me,
> > > so I won't have exactly Thomas' setup.
> > 
> > I've also run this on Arch with the cross compiler installed and
> > see no
> > issues. Thomas, can you look at the log below and see what differs
> > from
> > your setup?
> 
> I'm sorry for the noise.
> It compiles fine after cleaning the build directory :/

No worries, thanks for checking again!

-- 
Kind regards,
Luca Boccassi